LIFE HISTORY OF SHORTLEAF PINE. 7 



SIZE, AGE, AND HABIT. 



Over much of its range the average height attained by shortleaf is 

 between 80 and 100 feet, and in regions of better development 

 between 100 and 120 feet, with a maximum of about 130 feet. Mature 

 diameters of from 2 to 3 feet are most common; those of 4 feet are 

 rare except in trees grown in the open. The tree commonly reaches 

 an age of between 200 and 300 years, a maximum of about 400 years 

 being occasionally attained. 



In size, shortleaf holds about middle ground between longleaf and 

 loblolly pines. Loblolly grows to an equal height and a greater 

 diameter, but is not so straight a tree. Longleaf averages a little 

 higher, but has a somewhat smaller trunk at maturity. 



FORM. 



A long clear straight bole with small taper and short crown makes 

 shortleaf pine almost an ideal tree for the saw. These characteristics 

 are so much more pronounced in shortleaf than in several of its pine 

 associates, for example, pitch, scrub, and loblolly pine, that they 

 serve commonly as distinguishing marks. In early lif e the tree has 

 a narrow pyramidal stem, which later becomes more cylindrical (Pis. 

 I and II). Tables showing the form or taper of the stem, both out- 

 side and inside the bark, will be found in a forthcoming bulletin on 

 the importance and management of shortleaf pine. These include 

 tables for North Carolina and Arkansas, showing inside bark meas- 

 urements at intervals of 8.15 feet above a 1.5 foot stump for trees 

 from 40 to 120 feet in height and of corresponding diameter classes. 

 The tables are adapted for use in calculations of cubic volume of saw 

 timber from 8 and 16 foot logs, allowing 0.3 foot additional length for 

 each 16-foot log. The butt taper at 1-foot intervals of trees of vari- 

 ous diameters is also shown, and there is a table of tapers outside the 

 bark at 10-foot intervals above the ground for trees from 40 to 90 feet 

 in height. 



CROWN AND BARK. 



A short crown composed of numerous small branches, forming a 

 narrow pyramidal head, permits of the close density which charac- 

 terizes shortleaf-pine stands. This inherent narrow crown habit is 

 well shown in trees grown in the open, where it is conspicuous even 

 to an advanced age. Although changes take place in the relative 

 demand of the crown for light- after the period of maximum height 

 growth (about 50 to 70 years), the change in the general shape of the 

 crown is slight. While the crown of longleaf in early life has about 

 the same outline as shortleaf, though less dense, in later life it broadens 

 out far more. Loblolly maintains a much wider and heavier crown 

 at all periods of life than either of the other important southern 

 pines. This habit is more pronounced on the drier soils; hence in 



